Method and apparatus for communicating different types of data in a data stream

ABSTRACT

An apparatus and method is described for transmitting, receiving and communicating program data signals which are combined with digital data signals. Preferably, the present invention compresses 30 digital audio signals, multiplexes them with title, track, artist, record label, year, etc., program information, and transmits the combined signals via satellite to a receiving station. The receiving station demultiplexes the signals and sends them via a cable distribution system to a subscriber&#39;s digital music tuner. This tuner further demultiplexes and decodes the signals so that the digital audio signals may be converted to analog and output for listening, while the corresponding data signals are communicated to the subscriber. In an alternative preferred embodiment, the program data signals are transmitted to a remote control receiver where they are displayed. The system described in the present invention may be used for transmitting video, software or games with program data to subscribers.

This application is a continuation on Ser. No. 08/171,453 filed Dec. 22,1993, now abandoned which is a continuation of Ser. No. 08/056,560 filedMay 3, 1993, now U.S. Pat. No. 5,406,558 which is a division of Ser. No.07/618,744 filed Nov. 27, 1990, now U.S. Pat. No. 5,239,540.

TECHNICAL FIELD

The present invention relates to the field of digital signaltransmission and more particularly, to transmitting digital signalsaccompanied by pro,ram content data so that listeners/viewers may see adisplay of the program content data as they are listening/viewing theperformance, without interrupting the performance.

BACKGROUND OF THE INVENTION

Presently, program content information, for example, song title, artist,record label, etc., is communicated to the customer/listener byannouncers' disc jockeys (DJs). In the ease of video program transmittedby broadcast means, video text are presented between programs and duringinterruptions of program. In the ease of many premium services, it isundesirable to interrupt programs for presentation of program contentinformation. It may also be undesirable to have any form of announcer orDJ between program or selection of music.

Those such announcers or interruptions of program may be undesirable insome services. Nevertheless, it is highly desirable to communicateprogram content information. Frustration of customers, and possible lossof revenue due to subscription cancellation can occur if a subscriberhas no method of knowing the title composer or artist of the particularselection of music. To the music industry. identification of recordinglabel and identification number is critical to sale of the recordings.Currently, a subscriber viewing a premium video program must consult aseparate listing, tune to a different channel, or wait till the end ofthe program for its identification.

Similarly, the cable television industry is currently introducingaudio-only services. Program content information is printed in aseparate listing. These cable "radio stations" may play a continuoussuccession of musical selections without commercial interruptions. Theseservices may not use a "disc-jockey" to identify the musical or otherselections, Instead, under the present invention, data channels willcontain information about the music being played.

In one embodiment of the present invention, a display of this data hasbeen envisioned that has been termed an "electronic DJ". This displaycould be built into the subscriber terminal itself, or it could be aseparate display unit that would connect to a port on the rear panel ofthe terminal.

The problem with such displays is that, unless they are very large andtherefore costly, they cannot be easily placed within reading distanceof the listener. Long cables for the display would be difficult to routein a typical living room, and we need only look at the success of VCRwired remote controls to convince ourselves that such a tethered displaywould not be optimum.

Wireless remote controls have brought great convenience to the controlof consumer products. Highly intelligent remote controls with liquidcrystal displays are available. Programmable and universal "learning"remote controls are available that assume the functions of multipleother controls. These remote controls receive information from eachother, and display the functions available to the user.

It can be a frustrating experience to enjoy a piece of music on theradio, only to have the station fail to identify the piece. To lovers ofmusic, having such information as music title, composer, artist andrecord label is vital. Without this information, the service will bereduced to the level of generic background music.

SUMMARY OF THE INVENTION

The problems and related problems of transmitting and providing adisplay of program content data are solved by the principles of thepresent invention. In furtherance of these principles, it is an objectof the present invention to provide program information to subscriberswithout interrupting the program.

It is an object of the present invention to transmit and provide programinformation for digital audio transmitted to subscribers, where theprogram information is combined with the digital audio.

It is a further object of the present invention to provide program datato subscribers of video information.

It is another object of the present invention to provide program tosubscribers where the information is communicated through a remotecontrol unit.

It is a further object of the present invention to provide a systemwhere digital program information is combined with digital audio/videosignals which are transmitted via satellite, coaxial cable, or othermeans to subscribers.

It is another object of the present invention to provide program datacorresponding to audio/video signals to subscribers with disabilities.

In accordance with these and other objects, apparatus for encodingaccording to the present invention comprises: a plurality of means forproducing digital signals; a plurality ol means for producing aplurality of program data signals, each program data signalcorresponding to one digital signal; and, at least one encoding means,coupled to the plurality of means for producing digital and program datasignals, for encoding the plurality of program data signals with theplurality of digital signals to produce a plurality of combined digitaland program data signals.

Additionally, under these and other objects, a method is disclosed forencoding program information into a digital data stream comprising thesteps of: producing a plurality of digital signals: producing aplurality of program data signals, each program data signalcorresponding to one digital signal; and encoding the plurality ofprogram data signals with the plurality of digital signals to produce aplurality of combined digital and program data signals.

Conversely, under the above and other objects, an apparatus is disclosedfor communicating program information corresponding to a track ofdigital data from a signal containing a plurality of digital and programinformation signals comprising: first receiving means for receiving anencoded signal containing a plurality of digital signals and a pluralityof program data signal, each program data signal corresponding to onedigital signal; at least one selecting means, coupled to the firstreceiving means, for selecting one digital signal and one correspoondingprogram data signal from the received encoded signal; at least onedecoding means, coupled to the selecting means, for decoding theselected one digital signal and the one corresponding program datasignal so as to separate the corresponding program data signal from theselected one digital signal; transmitting means, coupled to the decodingmeans, for transmitting the one corresponding program data signal;second receiving means, coupled to the transmitting means, for receivingthe one corresponding program data signal; and, communicating means,coupled to the second receiving means, for communicating the onecorresponding program data signal.

Similarly, a method under the above objects is disclosed forcommunicating program information corresponding to a track from signalcontaining a plurality of digital and program information signalscomprising the steps of: receiving an encoded signal containing aplurality of digital signals and a plurality of program data signals,each program data signal corresponding to one digital signal; selectingone digital signal and one corresponding program data signal from thereceived encoded signal; decoding the selected one digital signal andthe one corresponding program data signal so as to separate thecoresponding program data signal from the selected one digital signal;transmitting the one corresponding program data signal to acommunicator; receiving the transmitted one corresponding program datasignal; and, communicating the received one corresponding program datasignal via the communicator.

Finally, under the objects of the present invention, a handheldapparatus for communicating program information corresponding to digitaldata is disclosed comprising: receiving means for receiving a programdata signal corresponding to a digital track; processing means, coupledto the receiving means, for processing the received program data signal;and, communicating means, coupled to the processing means, forcommunicating the processed program data signal.

The communicating means under the present invention could take the formof a standard remote control, i.e. a hand-held unit with a display ofsome sort. The display could be a liquid crystal or other suitabletechnology. A benefit of having the display in a remote unit under thepresent invention is that the cost of the display need not be includedin the base unit. The display can be a value-added extra-cost feature.It can thus be seen as a means of increasing revenue, or of making theservice more affordable to those not desiring the feature.

The communicating means under the present invention could also take theform of a table-mounted unit. It could use a larger display than mightbe possible on a hand-held remote. It could also use ac power instead ofbatteries and thus power a brighter and larger display more suitable forlow light viewing. The control and display functions could be separatedinto two individual units.

The base subscriber terminal could automatically update the remotedisplay/control unit whenever there has been a change in programming.This, however, may result in brief intervals during which the use ofother remote controls might be disrupted. Instead, the communicationsmay be structured such that for information to be sent from the basesubscriber terminal, it must be polled from the remote unit. Memorycould be used in either the base unit or the remote to store informationon previous selections. This information could be recalled by the useron demand.

The communications link between the base subscriber terminal and theremote unit could use radio frequencies, infrared, visible light,acoustical transmission through air, or other wireless means. Theconcept could also be extended to carrying the information on thehousehold power lines, telephone wires, coaxial cable fiber-optic cableor means other than the direct connection of a cable to the base unit.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other advantages of the present invention may be appreciatedfrom studying the following detailed description together with thedrawings in which:

FIG. 1 is a blocked diagram of the overall system in the presentinvention;

FIG. 2 shows a detailed block diagram of the encoding and transmitterportion of the present invention;

FIG. 3 shows a block diagram of the encoding portion of the presentinvention;

FIG. 4 shows a block diagram of the receiving portion of the presentinvention;

FIG. 5 shows a block diagram of the digital music tuner;

FIG. 6 shows a block diagram of the application specific integratedcircuit shown in FIG. 5;

FIG. 7 shows a block diagram for the remote communication device of thepresent invention; and,

FIG. 8 shows a diagram of a simplified frame format using the presentinvention.

DETAILED DESCRIPTION

Referring to FIG. 1, a block diagram of an overall system in the presentinvention is described. The present invention will be described withrespect to transmitting audio signals with program data. However, thoseskilled in the art will recognize that the present invention may,instead of transmitting audio with corresponding program data, transmitany of the following, with corresponding program data: television,games, software, video, and other combinations of audio/video orsoftware information.

Compact disc players 10-l through 10-n provide a plurality of digitalaudio signals to the present invention. These CD players may be the socalled "Jukebox" type wherein up to sixty or more compact discs may bestored and accessible by the player.

The digital audio signals from CD players 10-1 through 10-n are input toencoders 20-1 through 20-n which will be described in greater detailwith reference to FIG. 3. Controller and music database 30-1 through30-k controls the output of CD players 10-1 through 10-n and anyrespective selection of compact discs within these players and alsoprovides a database containing program data with a one to onecorrespondence to the tracks contained on the compact discs. Thisprogram data includes title, track, artist, publisher, composer, songidentification and play time information blocks for each song containedon a compact disc. These program data signals could also include otherinformation relevant to describing the particular track contained on acompact disc, as those skilled In the art can appreciate. For example,if the information were historical audio data, information on the timeand place such data was first conceived or transmitted may also becontained within this program information. Additionally, if the digitalsignals transmitted contained video information, the correspondingprogram data signals would relate to the video program beingtransmitted, for example, the title, actors, director, publisher, year,or other relevant information.

The plurality of digital audio signals inputted by the CD players 10-1through 10-n are combined in encoders 20-1 through 20-n with the programdata signals inputted by controller and music databases 30-1 through30-k. The combined signals from encoders 20-1 through 20-n are theninput ted into multiplexer 40 which combines the signals into a serialdigital data stream.

Additional signals may be combined with the digital audio and programinformation signals. Subscriber control 45 contains information onvarious subscribers who may receive the digital audio data produced bythe present invention. This subscriber information stored in subscribercontrol 45 is multiplexed with the digital audio and program datasignals in multiplexer 40, producing a serial digital data streamcontaining digital audio program information and national subscriberinformation.

The serial digital audio/program data stream from multiplexer 40 isinput into the digital satellite transmitter 50 and broadcast, viasatellite, to digital satellite receiver 60. However, those skilled inthe art will realize that any delivery system, not just satellitetransmission, may be used, such as cable television (CATV), microwavedistribution (MDS or MMDS), telephone systems, terrestrial broadcasts,and other coaxial or optical cable lines.

The previously described transmitter section will be more fullydiscussed with reference to FIG. 2, while the following receiver sectionwill be more fully described with reference to FIG. 4. Digital 70 whichin turns converts and sends the information to digital cable modulators75. The digital audio data is then added with signals from other cablemodulators in summing circuit 80 and sent over a cable distributionsystem.

The cable distribution system includes line amplifiers 90 for boostingthe signal and compensating for any line loss. System tap directs thecombined signal to a subscriber's premises and into digital music tuner100. Digital music tuner 100, more fully described with respect to FIG.5, selects the channel containing the digital audio and program datasignals. Additionally, digital music tuner 100 separates the digitalaudio signal from the program information signal. The digital audiosignal is converted to analog, amplified and output on a subscriber'saudio electronics, while the program information signal is processed andsent to a local display or remote using information display 200. Thedemultiplexing and decoding of the signals is discussed more fully withreference to FIG. 6. These displays then communicate to the subscriberthe particular program information corresponding to an audio trackcurrently being listened to by the subscriber. The remote musicinformation display is more fully described with respect to FIG. 7.

Transmitting Section

Referring to FIG. 2, a block diagram of the studio and transmitter, oruplink, section of the present invention is described. Compact discplayers 10-1 through 10-n are driven by microcomputers 15-1 through15-n. Microcomputers 15-L through L5-n could be IBM Model ATmicrocomputers. These microcomputers are in turn controlled by thestudio sequencing master controllers 30-L through 30-k. These mastercontrollers 30-L through 30-k include a database containing the programinformation described above. These master controllers are preferably IBMModel PS/2 microcomputers or other computers containing a 386 typemicroprocessors.

The digital audio output from CD players 10-1 through 10-n is input intoencoders 20-1 through 20-n along with program information supplied bymaster controllers 30-1 through 30-k. Encoders 20-1 through 20-ncombined the digital audio signals with the program data signals andoutput the combined signal to system data multiplexers 40-1 and 40-2.Preferably, the outputs or 30 encoders 20-1 through 20-30 are input intomultiplexers 40-1 and 40-2 where the signals are time divisionmultiplexed. Multiplexers 40-1 and 40-2 may include error correctionencoding using, for example, Hamming encoding or Bose ChaudhuriHocquenghen (BCH) encoding, or other error correcting/encoding methodsknown by those skilled in the art.

Billing system 47 includes subscriber information of the presentinvention and national control information and may be comprised of anIBM Model PS/2 microcomputer. The subscriber information and otherbilling system data would be contained within a large database withinbilling system 47. Typical billing system data could include, forexample, identity, location, etc. for subscribers and their currentbilling status. Billing system information from billing system 47 isinput into the system manager digital audio controller 45. Systemmanager 45 is preferably comprised of a series 8500 System Managermanufactured by Scientific Atlanta or a similar product. System managerdigital audio controller 45 controls master controllers 30-1 through30-k. Additionally, the system manager 45 may also input subscriber datafrom the subscriber database within billing system 47 into multiplexers40-1 and 40-2.

The subscriber information may be combined with the digital audio andprogram signals through multiplexers 40-1 and 40-2. Multiplexers 40-1and 40-2 provide the master clock to all the encoders 20-1 through 20-nand to satellite exciters 53-1 and 53-2. The output of multiplexers 40-1and 40-2 is a 34 megabits per second (Mbps) data stream comprising thepreferred 30 channels outputted by the 30 encoders 20-1 through 20-30.

Relay circuit 43 provides fault protection so as to switch the system tomultiplexers 40-2 and 40-2 from multiplexer 40-1 in event of a fault.The outputs from multiplexers 40-1 and 40-2 are two coaxial cables, forplus and minus balanced connections. These balanced coaxial cables areused from the output of multiplexers 404 and 40-2 through satellitetransmitting and receiving electronics. The combined signal frommultiplexer 40-1 passes through relay 43 into fiber-optic transmitter49. Fiber-optic transmitter 49 transports the signal from the studio tothe transmitter site and into fiber-optic receiver 51. The output of thefiber-optic receiver drives an offset quadrature phase shift keying(OQPSK) satellite modulator 50. The signal is then up converted,amplified and transmitted to the satellite, as more fully describedbelow.

The signals are received from fiber-optic transmitter 49 intofiber-optic receiver 51 in transmitter 50. From fiber-optic receiver 51the signals pass through fault protection relay 52-1 into Exciter 53-1.The digital signals from OQPSK exciter 53-1 enter splitter 57-1 andthrough fault protection relay 52-2. Thereafter, the signals passthrough an upconverter 58-1. From upconverter 58-1 the signals passthrough switch 56-1 into high powered amplifier 59-1 and once againthrough switch circuit 56-2 and then transmitted. The transmitting Ispreferably performed via a satelifted. The transmission may also occurvia coaxial cables or fiber-optic cables.

Redundancy control logic 55 controls transmitter 50, so in the event ofa fault, redundant circuitry is activated. Specifically, redundancycontrol logic 55 controls relays 52-1 and 52-2 and switches 56-1 and56-2 so as to switch to redundant exciter 53-2 and splitter 57-2,redundant up converter 58-2 and high powered amplifier 59-2.

Referring to FIG. 3, a more detailed block diagram of an encoder 20-1 isdescribed. Outputs from CD players 10 are input to multiplexer 31.Preferably the outputs from 16 CD players 10-1 through 10-16 are inputinto multiplexer 31 where their signals are combined and output as twochannels to rate synchronizers 33-1 and 33-2. The rate synchronizedsignals are then input into mixer and signal compressor 35. Mixer andsignal compressor 35 preferably uses the data compression formatdescribed in U.S. Pat. No. 4,922,537, incorporated herein by reference.Mixer and data compressor 35 is controlled by input signals from mastercontroller 30-1 which also inputs the program data signals correspondingto the digital audio signals. The digital audio signals are compressed,program data signals are, mixed therewith, and then the mixed signal isinput also include circuitry to encrypt the mixed and compressed signalsusing, for example, the Data Encryption Standard (DES) or using othersimilar encryption techniques known in the art. Circuit 37 may includeerror correction encoding using, for example, Hamming encoding or BoseChaudhuri Hocquenghen (BCH) encoding, or other error correcting/encodingmethods known by those skilled in the art. Hamming encoding is disclosedin Electronic Engineers Reference Book, edited by F. Mazda, page 32/10,incorporated herein by reference.

The audio data is clocked into and out of circuits 33-t, 33-2, 35 and 37at a rate of 44.1 kilosamples per second. The mixed compressed andencrypted signals are output of circuit 37 at 1.12896 Mbps inApplicant's preferred embodiment.

Receiving Section

Referring to FIG. 4, the mixed, compressed and encrypted signal isreceived in the C-band via Satellite receive antenna and amplified andblock converted in a low-noise block converter 63, along with othersatellite distributed signals. The signal is output in the L-band at 950to 1450 megahertz and input into splitter 65 where the audio signal isinput into OQPSK receiver 67. Receiver 67 demodulates the OQPSKinformation and provides one 34 Mbps signal stream containing thepreferred 30 satellite distributed channels. The 34 Mbps signal isoutput of receiver 37 at 34 megahertz clock rate into demultiplexer 70.Preferably, demultiplexer 70 is a 1:6 demultiplexer which separates thesingle data stream into six channels containing 5.6 Mbps digital audioand program data each. These six channels contain five stations each.

The signals are clocked at 11 megahertz to modulators 75-1 through 75-6.Each modulator 75-1 through 75-6 is a nine state quadrature partialresponse (9-QPR) modulator capable of handling five stations and eachoccupying a 3 megahertz bandwidth. Those skilled in the art willappreciate that one may also use phase shift key modulation or othermodulation methods known in the art with fewer or greater numbers ofstates.

The modulated signals from modulators 75-1 through 75-6 are combined inradio frequency combiner 80 along with other modulated signals fromother cable modulators 77. Modulators 75-1 through 75-6 digitally filterthe data, quadrature partial response (QPR) modulate and convert thedata to the selected output frequency for combining with other modulatedchannels 77 in the present cable television system. Each block of fivestereo pairs occupies 3 megahertz of band width and can be carried inhalf of one 6 megahertz video channel of the present cable televisionsystem. Since the present system uses a common 6 megahertz videochannel, no modifications of current CATV distribution system equipmentis required.

The combined signals from RF combiner 80 are distributed over a coaxialcable or fiber-optic distribution system into a subscriber's home.Directional coupler 85 directs most of the signal to video set topterminal 81. A sample of the signal is sent from directional coupler 85,at a loss of 10 decibels to digital music tuner 100. Tuner 100 iscontrolled by either a plain remote 201 or a music information displayremote 200. Additionally, tuner 100 outputs left and right analog audiosignals, and may also output an optional digital signal output.

Referring to FIG. 5, a block diagram of digital music tuner 100 isshown. The digital audio and program data signal is inputted fromdirectional coupler 85 into set top terminal tuner 110. This tunerpreferably includes phase locked loop circuitry. The signal from tuner110 is amplified by amplifier 115 and filtered by saw filter 120 beforebeing demodulated by demodulator 125. Tuner 110 converts the selectedradio frequency channel to a demodulation intermediate frequency. Theoutput of demodulator 125 is QPR demodulated to produce a 5.6 Mbps datastream containing five stereo pair of digital audio data to applicationsspecific integrated circuit (ASIC) 140. Demodulator 125 also provides anautomatic gain control signal 130 to tuner 110 to maintain constantsignal level. Additionally, demodulatot 125 provides data to clockrecovery phase locked loop (PLL) 135. Data clock PLL 135 contains a 33.8megahertz crystal 137 from timing purposes.

This timing signal is sent to ASIC 140, which will be discussed ingreater detail with reference to FIG. 6. ASIC 140 provides a digitalaudio output to interface 170. Interface 170 uses the Sony-Philipsdigital interface format (SPDIF). Similarly, the digital audio signalsare input from ASIC 140 to digital to audio converter 160. From digitalto audio converter 160, the analog left and right audio signals arefiltered through filters 165-1 and 165-2 and input into bypass 170.Bypass 170 allows additional audio components (e.g., a CD player or tapedeck) to be switchably connected with the digital music tuner 100.

Microprocessor 150 controls phase locked loop of tuner 110, ASIC 140,digital to analog converter 160 and bypass 170. The program data signalfrom ASIC 140 is sent to microprocessor 150 where it is stored ininternal memory of the microprocessor, and may be displayed on frontpanel interface 180 or transmitted through remote control transmitter190. Remote control receiver 195 may select particular program datainformation or audio channels through microprocessor 150.

Power supply 175 would supply both positive five volt digital and analogpower, and a negative five volt supply to the system. Positive 12 voltand positive 30 volt power supply signals are also provided from powersupply 175. Additionally, tuner 100 would preferably have input means,e.g., push buttons or toggle switches, on the exterior of its housing(not shown). These input means would allow selection of channels,stations, display of program data and display of particular informationblocks contained in The program data signal. Additional selections orinputs may be provided as those skilled in the art recognize.

Referring to FIG. 6, a more detailed block diagram of ASIC 140 isprovided. The signal from demodulator 125 is input into demodulatorsupport circuit 141 which comprises logic circuitry (e.g., flip-flops)required in demodulation of the signal. The signal from demodulatorsupport circuit 141 is then input into demultiplexer 143 which separatesthe 5.6 Mbps data stream to select one of five stereo pairs of digitalaudio signals. This signal is then sent to decrypting circuit 145. Thedecrypted signal is then separated in signal separator 148 where programdata is sent to microprocessor in/out circuit 149 while audio data issent and decoded in circuit 147. Decoder 147 uses the data decompressiontechnique described in U.S. Pat. No. 4,922,537, incorporated herein byreference.

Microprocessor in/out, address and control circuit 149 interfaces withmicroprocessor 150. All circuit within ASIC 140 are driver, by clock146. Memory 144 stores bits of data to support the demultiplexing,decrypting and decoding functions occurring in circuits 143, 145 and 147respectively. The memory may be of a nonvolatile type such as an EPROMor similar ROM memory or may be a volatile type RAM memory supported bybattery 175, preferably a lithium type battery. Such a battery 175 wouldprevent loss of data stored in memory 144.

Remote Display Unit

Referring to FIG. 7, a block diagram of the remote music informationdisplay unit 200 is shown. Program data signals are received by receiver201 from remote control transmitter 190. Preferably, infraredtransmitter and receivers 190, 195, 201 and 205 are used. However, radiofrequency, ultrasonic, wire, fiber-optic cables or other means could twoused as those skilled in the art can appreciate. The received signal isthen input into processor 203 which processes and sends the program datasignal to display 209 for communicating program data corresponding tocurrently playing audio track to a subscriber. Display 209 may be aliquid crystal display, a light emitting diode, a braille reader, avoice synthesizer or a cathode-ray tube or any other communicatingdevice as may be appreciated by those skilled in the art. Audible ortactile communicating means would allow communication of the programdata signals to subscribers with disabilities, as would the use of aremote unit.

Input means shown as keyboard 207 may receive program data selectioncommands or audio track commands from a subscriber which are sent toprocessor 203. Keyboard 207 may also include means to allow a subscriberto control volume, power, channel selection, station selection, display,or other suitable subscriber commands that those skilled in the artappreciate. Processor 203 then converts and transmits the subscribercommand signal to transmitter 205 which is received by remote controlreceiver 195. The received signal from receiver 195 is input intomicroprocessor 150 where appropriate signals are sent therefrom to ASIC140 and tuner 110 so as to bring about the subscriber's desired audiotrack, audio channel or program information.

Repeaters could be placed throughout a dwelling to extend the range ofthe display/control unit. Additionally, processor 203 could containmemory for storing various information, particularly programinformation.

In an alternative embodiment, the remote display unit may display only acode number representing the program data signals, whereby a subscribermay reference the number in printed material for a full description ofthe currently playing audio track. The printed material could be apublication which would rotate monthly or weekly as the programs onrespective stations change. Such a system would allow for a smallerdisplay on the remote unit, and thus be less costly to a subscriber.Such a printed publication would also allow a subscriber to determinewhich programs were playing on the various channels.

Additionally, the remote display unit or tuner 100 could display, upon asubscriber's request, program data corresponding to data beingtransmitted on channels not currently being listened to/viewed by thesubscriber. In this way, a subscriber may scan what is being broadcaston alternate channels while listening to a currently playing channel.

Data Format

The preferred thirty stereo audio stations are multiplexed as follows.Groups of five stations are formatted into a frame of data. Six suchframes are interleaved bit by bit for transmission over the satellite.Each such frame containing five stations has a header. This header isused by the headend demultiplexer 70 to deinterleave the satellitereceived data into six frame of five stations each. The header is alsoused in the ASIC 140 to synchronize on the frame. A second headercontains subscriber control transaction data. This second header wouldpreferably include channel and subscriber transaction data as previouslydescribed with respective billing system 47 The headers includeadditional bits for error detection.

Following the headers, compressed audio data with its associated programdata is sent. Audio data for each station includes a seven bit "kfactor" and a three bit "exponent" for each block of nine samples asdescribed in previously referenced U.S. Pat. No. 4,922,537. Five such kfactor and exponent blocks for each station are included in each frame.

The audio and program data for the five stations in the frame areinterleaved bit by bit. That is, the first bit is sent for station No.1, followed by the first bit for station No. 2 and so on until the firstbit of each station has been sent. Then the second bit of each stationis sent and so on. After the last audio data bits in each block of ninesamples have been sent, the program data bits are sent in the samemanner. Thus, the program data for each station is multiplexed in theframe with its associated station so that when the frame isdemultiplexed or rearranged, the program information for that station iskept with its station. The advantage of multiplexing the programinformation with the audio data is that one may easily process thecombined signal without fear of scrambling channels of audio data withtheir respective program information. Error correction and detectionbits are also sent with the audio data and the program data.

Two program data bits are sent in the same block together with everynine compressed samples (100 bits) of audio data. This effectivelyprovides a data channel of about 9800 baud used to transmit program datainformation. The information is sent in ASCII representation, but couldeasily be sent in other formats such as EBCDIC as would be apparent tothose skilled in the art. FIG. 8 shows the program information aspreferably sent and the size of each field in the present embodiment.Other information can be sent, such as music classification forselection of station by music type, special event announcements, orother such information, known by those skilled in the art.

We claim:
 1. A method for transmitting different types of data in asingle data stream comprising the steps of:generating digital data forinsertion into a data stream, said digital data including digital datarepresentative of at least one of games and software; generating a firsttype of data for insertion into said data stream; generating a secondtype of data for insertion into said data stream; combining said digitaldata with said fast type of data to form mixed data groups; generating aheader containing data from said second type of data; combining saidheader with said mixed data groups to form a data frame; andconstructing said data stream by joining a plurality of successive dataframes for transmission.
 2. The method of claim 1, wherein said firsttype of data comprises selection data which describes the attributes ofsaid digital data.
 3. The method of claim 1, wherein said second type ofdata includes subscriber control transaction data.
 4. The method ofclaim 1, wherein said second type of data comprises selection data whichdescribes the attributes of said digital data.
 5. The method of claim 1,wherein said first type of data includes subscriber control transactiondata.
 6. Apparatus for communication different types of digital data toa receiver comprising:first means for generating a first type of datafor insertion into a data stream; second means for generating a secondtype of data for insertion into said data stream; third means forgenerating digital data for insertion into said data stream, saiddigital data including digital data representative of at least one ofgames and software; means operatively associated with said first andthird means for combining said digital data with said first type of datato form mixed data groups; means operatively associated with said secondmeans for generating a header containing data from said second type ofdata; means for combining said header with a plurality of mixed datagroups to form a data frame; and means for constructing said data streamby joining a plurality of successive data frames for transmission. 7.The apparatus of claim 6, wherein said first type of data comprisesselection data which describes the attributes of said digital data. 8.The apparatus of claim 6, wherein said second type of data includessubscriber control transaction data.
 9. The apparatus of claim 6,wherein said second type of data comprises selection data whichdescribes the attributes of said digital data.
 10. The apparatus ofclaim 6, wherein said first type of data includes subscriber controltransaction data.
 11. A digital data receiver for receiving a datastream containing successive headers including data of a first type,with each header followed by a plurality of mixed data groups includingdigital data and data of a second type, said receiver comprising:firstmeans for detecting data of the second type from successive mixed datagroups contained in a received data stream; second means for detectingdata of the first type from successive headers contained in the receiveddata stream; means responsive to the detected data of the first type andthe detected data of the second type for recovering the digital datafrom the received data stream, the digital data including digital datarepresentative of at least one of games and software; and means forreproducing a program from the recovered digital data.
 12. The digitaldata receiver according to claim 11, wherein said first type of datacomprises selection data which describes the attributes of said digitaldata.
 13. The digital data receiver according to claim 11, wherein saidsecond type of data includes subscriber control transaction data. 14.The digital data receiver according to claim 11, wherein said secondtype of data comprises selection data which describes the attributes ofsaid digital data.
 15. The digital receiver according to claim 11,wherein said first type of data includes subscriber control transactiondata.